Fireplace heat exchange unit



FIG. 1 is a top front and right side perspective view of a fireplaceheat exchange unit showing my new design;

FIG. 2 is a front elevational view thereof on a reduced scale;

FIG. 3 is a rear elevational view thereof on a reduced scale;

FIG. 4 is a left side elevational view thereof on a reduced scale;

FIG. 5 is a right side elevational view thereof on a reduced scale;

FIG. 6 is a top plan view thereof on a reduced scale; and,

FIG. 7 is a bottom plan view thereof on a reduced scale.

The ornamental design for a fireplace heat exchange unit, as shown.